Mail processing equipment, such as, for example, a mailing machine, often includes different modules that automate the process of producing mail pieces. The typical mailing machine includes a variety of different modules or sub-systems each of which performs a different task on the mail piece. The mail piece is conveyed downstream utilizing a transport mechanism, such as rollers or a belt, to each of the modules. Such modules could include, for example, a singulating module, i.e., separating a stack of mail pieces such that the mail pieces are conveyed one at a time along the transport path, a moistening/sealing module, i.e., wetting and closing the glued flap of an envelope, and a metering module, i.e., applying evidence of postage to the mail piece. The exact configuration of the mailing machine is, of course, particular to the needs of the user.
One of the factors that determines the cost for shipping a mail piece to a destination is the weight of the mail piece. A mail piece could be, for example, an envelope, postcard, magazine, package, etc. The mailing machine will be provided with the weight of the mail piece, typically from an integral scale incorporated within the mail flow path, an external scale coupled to the mailing machine, or user input. Based on the weight of the mail piece, the postage rate and operator specified service option for a selected carrier, the mailing machine will determine the cost to deliver the mail piece to the destination. The mailing machine will then conduct an accounting procedure for the cost of shipping the mail piece and print an indicium evidencing payment of the postage. Mailing machines have traditionally been capable of printing postage indicia either directly on mail pieces, or on pieces of tape or a label, which are then attached to mail pieces.
For mailing systems that utilize an external platform scale, i.e., a scale that is independent and separate from the mail flow path, there are different methods that can be utilized for determining the weight of an item. In one method, referred to as single piece mode, the user places each mail piece onto the platform of the external scale, and the weight of the mail piece is provided by the scale to the controller of the mailing machine. The controller will calculate the cost for shipping the mail piece based on the weight of the mail piece provided by the scale. The user removes the mail piece from the scale and places it on the feed deck of the mailing machine base. Sensors detect the presence of the mail piece on the feed deck and the mail piece is automatically fed into the mailing machine for processing, or, alternatively, the user must press a start button for the mailing machine to transport the mail piece into the mail flow path. The user then repeats this procedure for each mail piece that the user desires to process.
Another method for determining the weight of a mail piece is referred to as a differential weighing method as disclosed in U.S. Pat. No. 5,001,648, which is hereby incorporated by reference. In accordance with the differential weighing method, a plurality of mail pieces are placed on an external scale coupled to a mailing machine and the collective weight of the mail pieces is registered. When the user removes a mail piece from the scale, the difference between the original collective weight of the mail pieces and the new collective weight of the mail pieces remaining on the scale is determined. The cost for shipping of the mail piece is calculated based on the determined differential weight. Sensors detect the presence of the mail piece on the feed deck and the mail piece is preferably automatically fed into the mailing machine for processing. The user then repeats this procedure for each mail piece that the user desires to process.
While conventional manual feed mailing machines generally work well utilizing the weighing methods as described above, there are some problems. For example, there are several ways in which mistakes made by the user in removing mail pieces from the scale and feeding the mail pieces into the mailing machine can result in the calculation and printing of incorrect postage for a mail piece. This is especially true if the mailing machine is being operated in a differential weighing mode and the user is attempting to process the mail pieces as quickly as possible. For example, the user may inadvertently remove two mail pieces at the same time. This would result in a single weight being calculated based on the combined weight of both of the removed mail pieces. If the user does not realize the mistake and places both of the removed mail pieces on the feed deck, only the first mail piece will be processed by the mailing machine, and an incorrect postage amount (which will be greater than necessary, thereby costing the user additional unnecessary postage fees), based on the weight of both mail pieces, will be printed on the mail piece. Since there will be no weight for the second mail piece, the postage for the second mail piece will not be calculated, and the second mail piece will not be fed into the mailing machine by the transport system. Thus, the second mail piece will simply sit on the feed deck of the mailing machine and no further operations will occur. The user may not be aware that two mail pieces were inadvertently removed from the scale together, and may believe that there is a problem with the sensors or feeding mechanism of the mailing machine. The user may be inclined to restart the entire system, which is time consuming, thereby decreasing the throughput of the mailing machine, or place a service call in the belief that the mailing machine is in need of repair. In either case, this can lead to general dissatisfaction with the mailing machine by the user.
Even if the user realizes that more than one mail piece was removed at the same time and attempts to replace one or more of the removed mail pieces back onto the scale such that only a single piece was actually removed, the problem may still not be corrected. For example, the inadvertently removed piece or pieces of mail may be added after the scale has stabilized and an incorrect weight reading, based on the weight of all of the removed mail pieces, has already been determined. The user will be unaware of the incorrect reading, which can result in either a loss of postage funds due to an incorrect amount of postage greater than required.
Another feeding and weighing error that can occur is if the scale has not stabilized sufficiently to provide a weight of the mail piece just removed before a subsequent mail piece is removed by the user. Such a situation could also result in a single weight being calculated based on the combined weight of both of the removed mail pieces, resulting in an incorrect postage value being printed on the first mail piece and the second mail piece not being processed by the mailing machine similarly as described above. Alternatively, this problem could result in the mailing machine being out of synchronization with the mail pieces. For example, the user may remove a third mail piece, and the mailing machine will use the weight of the third mail piece when processing the second mail piece.
Thus, there exists a need for a method and system that reduces feeding and weighing errors in a manually fed mailing machine.